Patients with idioparic pulmonary arterial hypertension may develop progressive exercise intolerance during childhood. Cyanosis can occur, if an atrial septal defect exists, allowing a right-to-left shunt. Typical physical findings include elevated jugular venous pressure with a giant "a" wave, right ventricular and pulmonary artery impulses, constant systolic ejection sounds at the upper left sternal edge, loud, single S2 at the upper left sternal edge due to early high pressure closure of the pulmonary valve and an S4 at the lower left sternal edge. No significant systolic murmur occurs unless tricuspid regurgitation develops. A high frequency, decrescendo, diastolic murmur immediately following S2 at the upper left sternal edge due to high pressure pulmonic regurgitation may occur.